How do I get the location for the first matching occurance of a regex, in a string? I need an expression that will take the regex /[0-9]/, find its first occurance in a string such as "_835A_Photo_descriptor.png". The point being that sometimes the first character of the file name is a number, sometimes it is not.

index is not good because I need to match a single digit, not a particular digit, thus regex.

I've tried pos, but that does not work, because of the m/xxx/g requsite, and besides, it does not give the beginning location, only where it last looked.

I'm trying @-, per perlvar.pod, but it does not seem to work.

I need this positional value, to evaluate other parts of the string.

foreach $filename (@curdirlist) {
#    print "$filename\n";  #sane
    if ( $filename =~ /([0-9])/ ) {
    ($startloc = @-) && ($alphaloc = $startloc + 4); }
    print "$startloc  ";
}

[download]

All $startloc s are printing 2, which is never correct given the sample set. It should be 0 or 1 only. (?) Most files start with a digit, some do not.

I stopped learning python because in my opinion, python does not natively support regular expressions, and I got tired of seeing how python works in MSDOS, which I do not use. Most of what I've done in the past has been with bash, sed and awk. But now I need more! More power imagne:<span style="text-decoration: underline;">NOW!!!</span>

So I'm learning perl. But I feel really stupid, like I'm missing the most obvious thing, on this problem.

David

In reply to position of first matching regex by techtaskers.com

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